Known contact duplication for magnetic tape is a thermal duplication method (see the Japan Electronic Communications Society, 1971 National Meeting, S9-7 and IEEE Transaction on Magnetics, Vol. MAG-20, No. 1, January 1984, p19-23, for example).
The thermal duplication method is to duplicate signals through thermal duplication by using a master tape in the form of a .gamma.-Fe.sub.2 O.sub.3 tape or the like, and moving the master tape and a CrO.sub.2 tape in mutual contact at a high speed, while heating at about 150.degree. C.
However, since the prior art CrO.sub.2 tape has no flat frequency response to duplication signals, the master tape must be recorded with emphasis.
Also, the CrO.sub.2 tape is inconvenient to handle in that it can be erased with conventional magnetic heads because CrO.sub.2 particles have a coercive force Hc as low as 0.4 to 0.7 kOe.
In turn, known high coercive force materials having a low Curie point include magnetic alloy particles such as MnBi.
In order to provide a high coercive force, these alloy materials, however, must have a Curie point of about 300.degree. C. or higher, which requires a higher heating temperature with the risk that the substrate can be thermally deformed and an output with deteriorated waveform will result.
Because of a low squareness ratio and a broad thermal demagnetization curve, the output varies with the varying temperature of the heating head. In addition, noises frequently occur and an output S/N ratio is low.
In addition, corrosion resistance and weathering resistance are insufficient.